Statistical Characterisation of Fetal Anatomy in Simple Obstetric Ultrasound Video Sweeps

• Published in: Ultrasound in medicine & biology Vol. 50; no. 7; pp. 985 - 993
• Main Authors: Gleed, Alexander D., Mishra, Divyanshu, Self, Alice, Thiruvengadam, Ramachandran, Desiraju, Bapu Koundinya, Bhatnagar, Shinjini, Papageorghiou, Aris T., Noble, J. Alison
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01-07-2024
• Subjects: Fetal presentation; Probabilistic; Standardized obstetric sweep protocols; Statistical priors; Ultrasound video sweeps; Statistical priors; Ultrasound video sweeps; Standardized obstetric sweep protocols; Fetal presentation; Probabilistic
• ISSN: 0301-5629; 1879-291X; 1879-291X
• DOI: 10.1016/j.ultrasmedbio.2024.03.006

We present a statistical characterisation of fetal anatomies in obstetric ultrasound video sweeps where the transducer follows a fixed trajectory on the maternal abdomen.
Large-scale, frame-level manual annotations of fetal anatomies (head, spine, abdomen, pelvis, femur) were used to compute common frame-level anatomy detection patterns expected for breech, cephalic, and transverse fetal presentations, with respect to video sweep paths. The patterns, termed statistical heatmaps, quantify the expected anatomies seen in a simple obstetric ultrasound video sweep protocol. In this study, a total of 760 unique manual annotations from 365 unique pregnancies were used.
We provide a qualitative interpretation of the heatmaps assessing the transducer sweep paths with respect to different fetal presentations and suggest ways in which the heatmaps can be applied in computational research (e.g., as a machine learning prior).
The heatmap parameters are freely available to other researchers (https://github.com/agleed/calopus_statistical_heatmaps).